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    basically diff indices
    6
    ----
    5x^3 + 4x^3
    now the 4x^3 bit is simply 12x squared but the six over 5x^3 is confusing me a bit, would it be just 6/5 times x^3 and then differentiate it. that seems too easy. any suggestions?
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    rewrite it as (6/5)(x^-3) + 4(x^3)
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    (Original post by El Stevo)
    rewrite it as (6/5)(x^-3) + 4(x^3)
    what i said then ok cool
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    (Original post by Mr. Brightside)
    basically diff indices
    6
    ----
    5x^3 + 4x^3
    now the 4x^3 bit is simply 12x squared but the six over 5x^3 is confusing me a bit, would it be just 6/5 times x^3 and then differentiate it. that seems too easy. any suggestions?
    d/dx {6/(5x^3) + 4x^3} = d/dx {(6/5)(x^-3) + 4x^3} = (6/5)(-3)(x^-4) + (4)(3)(x^2) = 12x^2 - 18/(5x^4) = (60x^6 - 18)/(5x^4)

    Nima
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    (Original post by Mr. Brightside)
    what i said then ok cool
    no... you said (6/5)*(x^3)... what i said has a very important difference... (6/5)*(x^-3)
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    (Original post by El Stevo)
    no... you said (6/5)*(x^3)... what i said has a very important difference... (6/5)*(x^-3)
    his

    6
    ----
    5x^3


    is 6/(5x^3) ?
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    yes... but his
    (Original post by Mr. Brightside)
    would it be just 6/5 times x^3 and then differentiate it
    is wrong...
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    oh yeh ok then.
 
 
 
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